§ 501-a. Actions against persons designated foster parents of the division; defense and indemnification. The provisions of § 17 of the public officers law shall apply to persons designated foster parents whose duties involve the care, treatment or supervision of persons admitted to institutions operated by the division, whether within such institutions or released therefrom pursuant to section five hundred twenty-three of this article or whose duties involve services to or for applicants while rendering such care, treatment or services.